An improved compact electroacoustic transducer and loudspeaker system. The electroacoustic transducer (or array of electroacoustic transducers) can generate the desired sound by the use of pressurized airflow. The electroacoustic transducer uses a shared stator with an array of vent support fingers and metal frame instead of two stators per electroacoustic transducer.

An improved compact electroacoustic transducer and loudspeaker system. The electroacoustic transducer (or array of electroacoustic transducers) can generate the desired sound by the use of pressurized airflow. The electroacoustic transducer uses a shared stator with an array of vent support fingers and metal frame instead of two stators per electroacoustic transducer.

An electret element includes: an electret film that contains silicon oxide; and a protective film formed over the electret film and constituted of aluminum oxide deposited through an atomic layer deposition method.

Improving noise rejection of a micro-electro-mechanical system (MEMS) microphone by utilizing a membrane sandwiched between oppositely biased backplates is presented herein. The MEMS microphone can comprise a diaphragm that converts an acoustic pressure into an electrical signal; a first backplate capacitively coupled to a first side of the diaphragm—the first backplate biased at a first direct current (DC) voltage; a second backplate capacitively coupled to a second side of the diaphragm—the second backplate biased at a second DC voltage; and an electronic amplifier that buffers the electrical signal to generate a buffered output signal representing the acoustic pressure.

The method of capturing an audio scene includes acquiring sounds having first and second directivities to obtain first and second acquisition signals, respectively, the first directivity being higher than the second directivity, the steps of acquiring being performed simultaneously, and both acquisition signals together representing the audio scene; separately storing the first and second acquisition signals or mixing individual channels in the acquisition signals to obtain first and second mixed signal, respectively, and separately storing the first and second mixed signals, or transmitting the first and second mixed signals or the first and second acquisition signals to a loudspeaker setup and rendering the first mixed signal or the first acquisition signal using a loudspeaker arrangement having a first directivity and simultaneously rendering the second mixed signal or the second acquisition signal using a loudspeaker arrangement having a second directivity, the second loudspeaker directivity being lower than the first one.

A microphone assembly comprising a housing, a single flexible diaphragm, and a rigid backplate. The backplate may be coated with a parylene configured to help reduce the flatness deviation of the backplate across the diameter of the backplate. A plurality of openings may extend from the top portion of the backplate to the bottom portion of the backplate.

An impedance matching method for an electret microphone is provided. In some embodiments, the impedance matching method includes collecting a bias voltage between a source and a drain of a field effect transistor built in the electret microphone; determining whether the bias voltage is within a preset bias voltage threshold range; and if it is detected that the bias voltage is not within the preset bias voltage threshold range, sending a corresponding control signal to adjust load bias impedance so that the bias voltage is within the preset voltage threshold. An impedance matching apparatus for an electret microphone and a communication device are also provided.

The disclosure provides a MEMS device. The MEMS device comprises a printed circuit board, a cover attached to the printed circuit board to form a housing, at least one sound hole formed in the housing, a transducer with a diaphragm inside the housing, and at least one shutter structure. Each shutter structure is mounted to the housing around a respective sound hole. Each shutter structure comprises a moveable component disposed near the inner surface of the housing, the moveable component remains at an open position under regular pressure such that an air flow path from the sound hole to the at least one ventilation hole of the substrate across the moveable component is opened, and moves to a first closed position under a high external pressure to block the at least one ventilation hole and close the air flow path.

An apparatus includes a microelectromechanical system (MEMS) device having a diaphragm and a back plate; a clipping circuit coupled to the MEMS device, wherein the clipping circuit is configured to clip an output signal of the MEMS device so that the maximum signal drawn by a buffer is substantially constant over a temperature range; and an integrated circuit coupled to the clipping circuit, the integrated circuit including the buffer.

Microelectromechanical systems (MEMS) electret acoustic sensors or microphones, devices, systems, and methods are described. Exemplary embodiments employ electret comprising an inorganic dielectric material such as silicon nitride in MEMS electret acoustic sensors or microphones. Provided implementations include variations in electret acoustic sensor or microphone configuration and recharging of the electret.